بررسي تأثير افزودن نانوذرات گرافن اكسايد بر خواص مكانيكي و بيولوژيكي سيمان كلسيم فسفاتي

Effect of Graphene Oxide Nanoparticles Addition on Mechanical and Biological Properties of Calcium Phosphate Cement

در مطالعه حاضر، تأثيرات افزودن نانو ذرات گرافن اكسايد بر خواص فيزيكي-مكانيكي-بيولوژيكي سيمان كلسيم فسفاتي مورد بررسي قرار گرفته است. پاسخ سلولي برروي رده سلوليMG63 و واكنش هاي بافتي پس از كاشت سيمان تقويت شده با نانو ذرات گرافن اكسايد در استخوان آهيانه موش صحرايي ويستار بررسي شد. سيمان كلسيم فسفاتي از نوع براشيتي از مخلوط كردن پودر بتا تري كلسيم فسفات و مونوكلسيم فسفات مونو هيدرات تهيه شد. افزودن گرافن اكسايد در غلظت هاي 0، 0.5، 2 و 5 درصد وزني به فاز سيمان كلسيم فسفاتي باعث كاهش زمان گيرش و افزايش قابل توجه استحكام مكانيكي (2 درصد وزني) شد. همچنين رشد بلورهاي جديد آپاتيتي پس از قرارگيري نمونه ها در محلول شبيه سازي شده بدن به مدت 7 و 14 روز مشاهد شد كه حاكي از زيست فعالي نمونه هاي تقويت شده با گرافن است. تصاوير ميكروسكوپ الكتروني روبشي از نمونه ها نشان داد كه سيمان تقويت شده با گرافن اكسايد چسبندگي سلول را تسهيل مي كند. علاوه بر اين، فعاليت آلكالين فسفاتاز در مقايسه با سيمان خالص بهبود يافته است. تجزيه و تحليل ارزيابي بافت شناسي نشان داد كه حضور گرافن اكسايد باعث افزايش كارايي استخوان زايي در مقايسه با سيمان خالص شد. از اين رو، مي‌توان نتيجه گرفت كه سيمان براشيتي در تركيب با گرافن اكسايد با درصد مشخص، باعث تقويت خواص مكانيكي و بيولوژيكي آن مي شود و گزينه ي مناسبي در درمان هاي باليني استخوان محسوب شود.

In the present study, we have evaluated the effects of graphene oxide (GO) addition on the physical-mechanical-biological properties of calcium phosphate cement (CPC). The in vitro cellular responses of MG63 and in vivo tissue responses after the implantation of CPC/GO in parietal bone defects of wistar rats were also investigated. The brushite calcium phosphate cements were prepared by mixing β-tricalcium phosphate [β-TCP, Ca3(PO4)2] and monocalcium phosphate monohydrate [MCPM, Ca(H2PO4)2. H2O]. Inclusion of GO at the concentration of 0, 0.5, 2 and 5 wt% resulted in marginal decrease in setting time and significantly enhanced the compressive strength. New Ca-deficient apatite layer was deposited on the composite surface after immersing in SBF for 7 and 14 days. Field emission scanning electron microscope (FESEM) images indicated that GO incorporated brushite cement facilitates cell adhesion. In addition, alkaline phosphatase (ALP) activity of cells was improved compared with the pure CPC. Histological evaluation analysis showed that CPC/GO enhanced the efficiency of new bone formation in comparison with CPC. We concluded that CPC/GO can overcome the flaws of previously developed natural CPCs and be potential candidates as bone cements for clinical application of bone repair and regeneration. KEYWORDS: calcium phosphate cement, graphene oxide, osteogenesis. In the present study, we have evaluated the effects of graphene oxide (GO) addition on the physical-mechanical-biological properties of calcium phosphate cement (CPC). The in vitro cellular responses of MG63 and in vivo tissue responses after the implantation of CPC/GO in parietal bone defects of wistar rats were also investigated. The brushite calcium phosphate cements were prepared by mixing β-tricalcium phosphate [β-TCP, Ca3(PO4)2] and monocalcium phosphate monohydrate [MCPM, Ca(H2PO4)2. H2O]. Inclusion of GO at the concentration of 0, 0.5, 2 and 5 wt% resulted in marginal decrease in setting time and significantly enhanced the compressive strength. New Ca-deficient apatite layer was deposited on the composite surface after immersing in SBF for 7 and 14 days. Field emission scanning electron microscope (FESEM) images indicated that GO incorporated brushite cement facilitates cell adhesion. In addition, alkaline phosphatase (ALP) activity of cells was improved compared with the pure CPC. Histological evaluation analysis showed that CPC/GO enhanced the efficiency of new bone formation in comparison with CPC. We concluded that CPC/GO can overcome the flaws of previously developed natural CPCs and be potential candidates as bone cements for clinical application of bone repair and regeneration